1. Field of the Invention
The present invention relates to a semiconductor device for mounting a semiconductor element on a substrate by a face-down bonding and a method for manufacturing the same.
2. Description of the Related Art
A recently advanced semiconductor manufacturing technique achieves a semiconductor element having over 100 electrode terminals. In the achievement of the semiconductor element, there is a growing demand for the technique of effectively bonding the electrode terminals of a high integration density semiconductor element to a wiring layer which is formed on an insulating substrate.
Japanese Patent Disclosure (KOKAI) Nos. 62-132331 and 62-169433 disclose the face-bonding technique for bonding a large number of electrodes of a semiconductor element, all at a time, on a wiring layer which is formed on a substrate. In these Disclosures (KOKAI), subsequent to coating a resin on a wiring layer-equipped substrate, bumps which are formed on the electrode of the semiconductor element are placed on the wiring layer in an aligned fashion, and the resin is cured while pressing the semiconductor element against the substrate side to obtain a bond between the bumps on the semi-conductor element side and the wiring layer on the substrate.
However, the aforementioned methods have encountered the following problems. That is, since an electrical/mechanical bond is achieved between the bumps on the semiconductor element and the wiring layer on the substrate after the resin has been cured, if pressing the semiconductor element against the substrate is stopped prior to curing the resin, then there is a possibility that there will be no conduction between the bumps and the wiring layer due to a regaining action of the resin. Further, no conduction is caused due to the penetration of the resin per se into a spot between the bumps and the wiring layer. Such a pressing step cannot be released prior to curing the resin and it is necessary to, subsequent to aligning the bumps with the wiring layer, continue the pressing operation until the resin is cured. Since, therefore, a high-cost mounter equipped with the position aligning mechanism requires a longer operation time, a poor productivity results. In the event of the occurrence of semiconductor element faults or mount faults, the resin which has once been cured has to be removed from the bonding site for replacement by a normal semiconductor element. It is, thus, very difficult to repair the defective semiconductor device.
Since, in the prior art, the semiconductor element is face-down bonded on the substrate subsequent to curing the resin, no adequate electrical bond is obtained between the electrode on the semiconductor element and the wiring layer on the substrate and hence a bond is effected with less reliability. The conventional method requires continuing a pressing operation until the resin is cured and also removing the resin from the deposited site for replacement by a semiconductor element. It is, therefore, very difficult to make repairs.